James had to leave the court in the the final minutes of Thursday’s NBA Finals game because of cramps - the result of the air conditioning system in the San Antonio Spurs’ arena failing and temperatures soaring to more than 90 degrees in the building.

If it was only 90 degrees in a stock car.

Temperatures have climbed to more than 130 degrees inside a car. Modern conveniences - air conditioning units and devices to blow cool air on the driver - make it easier but there are still days when the heat is nearly too much for a driver.

It happened to Johnson a few years ago at Daytona when he was skipping between his stock car and a road race car.

Johnson said he “got behind” on his hydration and then the electrical system in the road racing car failed. He was so worn out that he couldn’t push the brake pedal hard enough and missed the chicane on the backstretch during the road race. It was then he came to pit road to get out of the car.

It got worse for Johnson. About an hour later while in his motorhome alone, he suffered cramps and couldn’t move.

“I actually went into a full body cramp and was stranded inside my motorhome lying on the floor,’’ Johnson said. “Every muscle in my body locked up. I could barely get to my phone, which was on the table. I knocked it off. I don’t know if you have ever had a cramp, but try dialing a phone with everything like it is.’’

He phoned teammate Jeff Gordon, parked in the motorhome beside him but Gordon didn’t answer. When Gordon called back, Johnson yelled to get to his motorhome immediately.

“As he came in my bus, it took him about two or three minutes to stop laughing at me,’’ Johnson said of Gordon. “Then he got me to the care center, and three IV bags later I felt like myself again.’’

Matt Kenseth also knows the pain of driving a hot car. He still has a reminder of his first Nationwide race on his foot.

“(I) burned my heel the size of a 50-cent piece and that never really heals after that, so that’s not a lot of fun,’’ Kenseth said. “It’s like getting bad frostbite, your heel’s always messed up since that first one. I remember the first couple years getting the big blisters on your heels it would be so hot.”

Carl Edwards said that he’s found that it is about 40 degrees warmer in the car than the ambient temperature.

Edwards said the “most shocking” moment with how hot it got inside a vehicle came in his first Camping World Truck Series race.

“I remember at one point they threw the caution and I couldn’t see what the caution was for and I thought I’m on fire,’’ Edwards said. “It was so hot. I don’t think it’s ever gotten any better, you just get used to the heat.’’

Consider that his Ricky Bobby moment. You know the time when Will Ferrell’s character thought he was on fire in “Talladega Nights.”

“That was my first Ricky Bobby moment,’’ Edwards said. “At Dover, I was lifting my heels off the floor down the straightaways just because it’s burning your heels. Those guys back in the day, without the fans and the ducts, those we were some men.’’